tapered shaft

例句：

1. 1. The machine has a taper shaft that allows it to rotate smoothly.
   这台机器有一个渐缩轴，可以平滑地旋转。
2. 2. The car's engine has a taper shaft that reduces vibration.
   汽车的引擎有渐缩轴，可以减少振动。
3. 3. The drill bit has a taper shaft that makes it easier to hold and control.
   钻头有渐缩轴，使得握持和控制更容易。